Define a Blockchain interface

lib/blockchain.ts

@@ -0,0 +1,136 @@
+import * as util from 'ethereumjs-util'
+import BN = require('bn.js')
+
+/**
+ * This can be removed once
+ * [this PR](https://github.com/ethereumjs/ethereumjs-block/pull/72/files) gets merged, released,
+ * and ethereumjs-block is updated here.
+ */
+export type Block = any
+
+export interface Blockchain {
+  /**
+   * Adds a block to the blockchain.
+   *
+   * @param block - The block to be added to the blockchain.
+   * @param cb - The callback. It is given two parameters `err` and the saved `block`
+   * @param isGenesis - True if block is the genesis block.
+   */
+  putBlock(block: Block, cb: any, isGenesis?: boolean): void
+
+  /**
+   * Returns a block by its hash.
+   */
+  getBlock(hash: Buffer | BN, cb: (err: Error | null, block?: Block) => void): void
+
+  /**
+   * Iterates through blocks starting at the specified iterator head and calls the onBlock function
+   * on each block.
+   *
+   * @param name - Name of the state root head
+   * @param onBlock - Function called on each block with params (block, reorg, cb)
+   * @param cb - A callback function
+   */
+  iterator(name: string, onBlock: any, cb: any): void
+
+  /**
+   * Deletes a block from the blockchain. All child blocks in the chain are deleted and any
+   * encountered heads are set to the parent block.
+   *
+   * @param blockHash - The hash of the block to be deleted
+   * @param cb - A callback.
+   */
+  delBlock(blockHash: Buffer, cb: any): void
+
+  /**
+   * This method is only here for backwards compatibility. It can be removed once
+   * [this PR](https://github.com/ethereumjs/ethereumjs-block/pull/72/files) gets merged, released,
+   * and ethereumjs-block is updated here.
+   *
+   * The method should just call `cb` with `null` as first argument.
+   */
+  getDetails(_: string, cb: any): void
+}
+
+export class MockBlockchain implements Blockchain {
+  private readonly _blocks: Block[] = []
+  private readonly _blockNumberByHash: Map<string, number> = new Map()
+
+  putBlock(block: any, cb: any): void {
+    const blockNumber = util.bufferToInt(block.header.number)
+
+    if (this._blocks.length !== blockNumber) {
+      cb(new Error('Invalid block number'))
+      return
+    }
+
+    this._blocks.push(block)
+    this._blockNumberByHash.set(util.bufferToHex(block.hash()), blockNumber)
+
+    cb(null, block)
+  }
+
+  delBlock(blockHash: Buffer, cb: any): void {
+    const blockNumber = this._blockNumberByHash.get(util.bufferToHex(blockHash))
+
+    if (blockNumber === undefined) {
+      cb(new Error('Block not found'))
+      return
+    }
+
+    for (let n = blockNumber; n < this._blocks.length; n++) {
+      const block = this._blocks[n]
+
+      this._blockNumberByHash.delete(util.bufferToHex(block.hash()))
+    }
+
+    this._blocks.splice(blockNumber)
+    cb(null)
+  }
+
+  getBlock(hashOrBlockNumber: Buffer | BN, cb: (err: Error | null, block?: Block) => void): void {
+    let blockNumber: number
+
+    if (BN.isBN(hashOrBlockNumber)) {
+      blockNumber = hashOrBlockNumber.toNumber()
+    } else {
+      const hash = util.bufferToHex(hashOrBlockNumber)
+
+      if (!this._blockNumberByHash.has(hash)) {
+        cb(new Error('Block not found'))
+        return
+      }
+
+      blockNumber = this._blockNumberByHash.get(hash)!
+    }
+
+    cb(null, this._blocks[blockNumber])
+  }
+
+  iterator(name: string, onBlock: any, cb: any): void {
+    let n = 0
+
+    const iterate = (err?: Error | null) => {
+      if (err) {
+        cb(err)
+        return
+      }
+
+      if (n >= this._blocks.length) {
+        cb(null)
+        return
+      }
+
+      onBlock(this._blocks[n], false, (err?: Error | null) => {
+        n += 1
+        iterate(err)
+      })
+    }
+
+    iterate(null)
+  }
+
+  getDetails(_: string, cb: any): void {
+    cb(null)
+  }
+}

lib/evm/eei.ts

@@ -1,7 +1,7 @@
 import BN = require('bn.js')
 import { toBuffer } from 'ethereumjs-util'
 import Account from 'ethereumjs-account'
-import Blockchain from 'ethereumjs-blockchain'
+import { Blockchain } from '../blockchain'
 import Common from 'ethereumjs-common'
 import PStateManager from '../state/promisified'
 import { VmError, ERROR } from '../exceptions'

lib/index.ts

@@ -1,6 +1,5 @@
 import BN = require('bn.js')
 import Account from 'ethereumjs-account'
-import Blockchain from 'ethereumjs-blockchain'
 import Common from 'ethereumjs-common'
 import { StateManager } from './state'
 import { default as runCode, RunCodeOpts } from './runCode'
@@ -9,6 +8,7 @@ import { default as runTx, RunTxOpts, RunTxResult } from './runTx'
 import { default as runBlock, RunBlockOpts, RunBlockResult } from './runBlock'
 import { EVMResult, ExecResult } from './evm/evm'
 import runBlockchain from './runBlockchain'
+import { Blockchain, MockBlockchain } from './blockchain'
 const promisify = require('util.promisify')
 const AsyncEventEmitter = require('async-eventemitter')
 const Trie = require('merkle-patricia-tree/secure.js')
@@ -35,7 +35,7 @@ export interface VMOpts {
    */
   state?: any // TODO
   /**
-   * A [blockchain](https://github.com/ethereumjs/ethereumjs-blockchain) object for storing/retrieving blocks
+   * A blockchain object for storing/retrieving blocks
    */
   blockchain?: Blockchain
   /**
@@ -105,7 +105,7 @@ export default class VM extends AsyncEventEmitter {
       this.stateManager = new StateManager({ trie, common: this._common })
     }
 
-    this.blockchain = opts.blockchain || new Blockchain({ common: this._common })
+    this.blockchain = opts.blockchain || new MockBlockchain()
 
     this.allowUnlimitedContractSize =
       opts.allowUnlimitedContractSize === undefined ? false : opts.allowUnlimitedContractSize
@@ -116,7 +116,7 @@ export default class VM extends AsyncEventEmitter {
    *
    * This method modifies the state.
    *
-   * @param blockchain -  A [blockchain](https://github.com/ethereum/ethereumjs-blockchain) object to process
+   * @param blockchain - A blockchain object to process
    * @param cb - the callback function
    */
   runBlockchain(blockchain: any): Promise<void> {

lib/runBlockchain.ts

@@ -1,4 +1,4 @@
-import Blockchain from 'ethereumjs-blockchain'
+import { Blockchain } from './blockchain'
 import VM from './index'
 const async = require('async')
 

package.json

@@ -52,7 +52,6 @@
     "core-js-pure": "^3.0.1",
     "ethereumjs-account": "^3.0.0",
     "ethereumjs-block": "~2.2.0",
-    "ethereumjs-blockchain": "^4.0.1",
     "ethereumjs-common": "^1.3.0",
     "ethereumjs-tx": "^2.1.0",
     "ethereumjs-util": "^6.1.0",
@@ -74,6 +73,7 @@
     "@types/node": "^11.13.4",
     "browserify": "^16.2.3",
     "coveralls": "^3.0.0",
+    "ethereumjs-blockchain": "^4.0.1",
     "ethereumjs-testing": "git+https://github.com/ethereumjs/ethereumjs-testing.git#v1.2.7",
     "husky": "^2.1.0",
     "karma": "^4.0.1",